Two is one, one is none

529256_10100692241679249_1652425915_nAt an endurance event, the most critical component is hydration. For most endurance events, on course aid is at a minimum except at a few key points, and therefore carrying your own hydration is critical.

Given the importance of hydration, you do not want to rely on a single source. For this reason, I always carry multiple options, the exact breakdown of which varies depending on the style of the event.

For solo events, such as GORUCK Selection, Death Race, or events like those coming online from the Endurance Society, it is critical to have a back up source of water in case one breaks. If you’re miles away from a water source and your main bladder breaks, not only are you without a receptacle but you are out of water.

For that reason, for these types of events I will carry

At my drop box (if the event supports that) I typically also have additional bladders and Nalgene’s, kept filled and ready to go. Now if my main Source bladder breaks, I can take the spare, fill it from my Nalgene, and move on.

For team events (such as GORUCK Heavy or a GORUCK Challenge), the Nalgene isn’t necessary, as in an emergency scenario you can always take sips from a team mates water source. That said, I still always carry an empty spare bladder.

I’ve had to resort to spares on a number of occasions, sometimes to help others, sometimes due to failures of my main source.

Priority of Concerns

The spare is particularly useful during sub-zero events. In the event that your primary bladder freezes, you can easily switch it out to your spare. For winter events the order in which components of your bladder freezes will be dependent upon both the exposure to outside air, and the quantity of water present. The lesser the volume of water present, the quicker it will freeze

  1. The mouthpiece/nozzle – this is usually the most exposed item, contains a very small volume of water in the crevices of the component and can freeze really quickly
  2. The tube between the bladder and the nozzle – with a large surface area relative to a small volume of water, this can freeze easily.
  3. The main bladder itself. Containing a large volume of water, that sloshes around during movement, this actually takes a long time to freeze.

For this reason I will typically carry spare/dry Source mouthpieces which are easily switched out on the fly. I will repeat my packing list at the end of this article

Reducing The Odds of a Freeze

During the event, especially as temperatures drop significantly below freezing, it is critical to keep water away from the easily freezing components and in the main bladder. Achieving this is really simple. After taking a drink from the bladder, you can expel the liquid from the mouthpiece and tube by blowing air back into the main bladder.

Using this technique it is still recommended that you mitigate freezing further. Source hydration tubes come with a level of insulation, but you can add additional insulation sleeves to slow the rate of temperature loss. Additionally you can obtain or make a cover for the mouthpiece to do the same thing (for example this one from Geigerrig). I, however, will instead always tuck the mouthpiece into my jacket, or upper layers, to ensure it stays above freezing point.

Finally you will want to keep the main bladder as close to your body as possible so that residual body heat will slow the freezing process. Pack accordingly, but make sure you can still quickly access the water bladder to refill.

A quick tip to prevent problems with a nalgene freezing is to carry it upside down, so the cap doesn’t freeze to the top of the bottle.

And thats pretty much it. With the right equipment, and the above simple techniques, you can stay hydrated during your winter event, and have enough backup equipment without adding bulk or weight.

The Equipment

Source Hydration Bladder.

There are many products in the Source portfolio, and they are all designed to a military grade and offer a no-nonsense replacement warranty if they break. Hydration bladders break all the time, but in my experience, Source break WAY less than any other brand. I’ve blown at least a half dozen camelbak bladders but have only had one source bladder issue, and that was during a particularly arduous event.
Additionally it is really easy to get spare parts for Source equipment from Amazon.com. GORUCK also exclusively stock Source bladders on their site if you really need another stamp of approval…

I recommend getting either of the following products

Source Components (spares)

As mentioned, I like to carry spare tubes and mouthpieces. These are REALLY easy to switch out with the Source system. Just pop a button and the mouthpiece clicks out of the tube if it freezes up (which is a likely occurence)

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There are a number of options with a Nalgene bottle, the main one being wide or narrow mouthed. ALWAYS get the wide mouth, as it is more versatile and more easily fillable. It is, however, easier to drink from a narrow mouth on the move. For that reason I like to add a replacement cap that allows the best of both worlds.

Hydration Packing List Recap

  1. Source hydration bladder w/tube (filled)
  2. Source hydration bladder w/tube (empty/spare)
  3. Spare Source hydration tube (sub-freezing conditions only)
  4. Spare Source hydration mouthpiece (sub-freezing conditions only)
  5. Wide mouth Nalgene
  6. Nalgene replacement cap, wide-to-narrow mouth

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Good luck, and don’t freeze!

One thought on “Hydration at Sub-Zero

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